Chuck



E. BRIGHT.

. CHUCK.

APPLICATION FILED APRv 23, 1917. RENEWED SEPT. 9, 1921 1,420,682 Patented June 27 1922 2 SHEET3 SHEET 1 5 n uc IMO z,

am g w F. E; BRIGHT.

CHUCK.

APPLICATION HLED APR. 23, 1911. RENEWED same. 1921 Patented 51111627; 1922..

UNETE f annex. a

To all whom it may concern:

-Be it known that I, FRED E. BRIGHT, a citizen of the United Stategresidingat' New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Chuck's, of which the following is a specification, reference being had therein to the accompanying drawing; 7

, This invention relates to Workholding.

' chucks and has reference more particularly to chucks for supporting or holding annular work forms such as rings, cylinders and the like in orderthat the'external surface of the same may be subjectedto forming, grinding, finishing and similar operations.

The invention is designed with specialreference for use in handling the casing me s: of antifriction bearings, the object being to provide a chuck in which the'ring may be firmly and. powerfully held against .spring, and in true centered position relative'to the a' xis' of rotation of the chuck.-

With these and others objects in view my invention consists of a chuck comprising a body adapted to be mounted for rotation aboutan axis,.a plurality of expanding holding ja'ws mounted therein and provided with axially extending projecting portions adaptedto' act on the interior of the work so as to expose its outer surface, and an actuating memberfor the jaws operable to expand and force the sameoutwardly in forcible engagement with the interior of the work, the said jaws and actuating member being of such improved relative formation that the projectingportions of the jaws will be firmly and rigidly supported, and the work held thereby will be effectually prevented from springing or displacement.

.The invention consists also in an actuating member in the form of a plunger movable axially and engaging the jaws to expand them, the said plunger being formed withalon'gitudinal'ly extending grooves in which the jaws extend. I

Also the invention consists in forming the plunger and jaw" with cooperating sloping surfaces adapted, when the plunger is moved Specification o e s iit t- ,Patent'ed J une 27, "1922. Application filed April 23, 1917, Seria1 110.163.823. Renewed September 9, 1921., Serial n6. 499,54e. f

The invention i eria a the details of-construction" and" combination of'parts I r I the same wlth the work piece omitted:

Fig. 3' is a longitudinal sectionalelevation through the chuck-on anenlarged scale;

Fig. A is a front-perspective view of the actuating plunger showing'the grooves therein in which the jaws engage. o Fig. 5 is a front-perspective view of the ja"ws.- Fig. 6 is a longitudinal section on the line 66 of Fig. 1 showing means for holding the operating pingposition;

Fig. 7, is anele holding means' Referring tothe'drawings": 1 indicates a body or head of circular disk of one plunger w th the-jaws in gripvation'of a detail of said" like form and suitably formedsothatit'j'may be mounted in the machine and rotated aboutits central axis. The body is'proyided with a central circular opening 2 extending axially therethroug'handat its front it is H provided with a pliurality of (in the present instance 3) radially extending undercut or dovetail guiding slots *4 which extend through the front :face of theibody and which communicate at their under ends-withthe central opening therein. 5' indicates work-holding jaws, one guided ine'ach gu-id-' ing slot. Eachljaw consists of theradia'lly"v extending stem or bodyportion 5 corresponding in cross section tothe cross sectional form of the guiding slot and mounted therein, and alateral activeportion or jaw proper '5 on the inner end of the stem, which several jaws proper are convex on their outer sides so as to engagean'd fit the concave surface of the interior of the work piece A. The jaws thusmOu-ntedjare mov Y able to and from theiaxial centre of rotation proper extending in an axial direction beof. the chuck, the lateral portions or jaws r operated on may be passed over the jaws and held firmly in position when the jaws are expanded or moved outwardly radially.

in order that the jaws may be thus expanded and uniformly forced outward against the interior of the work, and in order that the jaws will be powerfully supported against spring, I provide an actuating member 6 in the present instance in the form of a plunger of circular form and cross section to snugly fit the circular opening in the chuck body. This plunger is formed with three grooves 7, one for each jaw, extending longitudinally thereof, the bottoms of which grooves-slope or incline rearwardly and outwardly, and' which grooves receive the inneredges of the jaws proper, the inner sides of which are beveled or lncllned to correspond to the bottoms of the grooves. As a result of this construction, when the plunger is thrust forwardly, the sloping surfaces of the grooves cooperating with those on the jaws, will cause the jaws to be forced outwardly radiallyand expanded in a uniform manner, and the outer surfaces caused to bind tightly against the interior of the work; whereby the work will be held firmly in position in a plane parallel with the plane of the face of the chuck body and will be truly centered with reference to the axis of I rotation of the latter. I

I ed from spring or displacement in the operation of the forming, shaping or grinding mechanisms thereon. Due to the extension of the inner edges of the jaws proper in the grooves in the plunger, and due to the fit of the latter in the circular opening in the chuck body, this opening is completely closed by the jaws and plunger so that the entrance of grindings, chips or dust or other foreign matter to the interior working parts of the chuck will be effectually prevented.

- The plunger may be operated to expand the aws in any suitable manner either by an air piston connected with a rod 6 attached to the plunger, or by a hand operated screw or otherwise, these operating means not being illustrated as they form no part of the present invention. i

F or the purpose of forcing the jaws inwardly to release the work when the plunger is retracted, I provide the radial stem of each jaw with a pin '7 extending rearwardly from near the outer end of the stem into a radial recess 8 formed in the chuck body and forming a rearward continuation of the guiding slot at its outer end. A spiral spring, 9 is seated in the recess with its inner end bearing against the pin and its outer end bearing against a plug 10 screwed in the outer end of the recess. These springs tend to urge the jaws forwardly and when the plungeris retracted they will act to'force the jaws inwardly and release the work.

The same result may be accomplished but in a positive manner by forming the sloping surfaces on the jaws and plungers with interlocking T-shape slots and ribs as shown by dotted lines in Fig. 2, the result being that when the plunger is retracted, it will positively draw the jaws inwardly and thus release the work.

Due to the support of the projecting jaws proper by the plunger extending between the same, the jaws may have considerable overhang without dangerof spring or displacement. This willpermit of the location of the work and its support by the jaws, at a considerable distancebeyond the face of the body so that the work may bepresented with its three sides exposed to'be op erated on. In setting the work in position on the jaws a slotted distance washer or plate B is first slipped over the jaws and seated against the same and then the work set in place around the jaws and against the distance washer, and after the jaws are expanded within the work and its position fixed, the distance piece may be removed.

In order to hold'the operating plunger so as to maintain the jaws in their gripping position, in cases where the'plunger is operated by fluid pressure and in the event of the failure of the pressure to maintain the plunger in its forwardposition, I propose to adopt the construction shown more particularly in Figs. 1 and 6 where it will be seen that a stem 11 is screwed'into a threaded opening 12 in the forward end of the plunger and is provided with an annular shoulder 13 which bears against a slotted washer 14 surrounding the stem and engaging the outer ends of the jaws. 5. By

screwing this stem into the threaded open be attained. It will be' manifest however that various changes may be made in the details without departing from the spirit of my invention and it. will 'be understood that the invention is not limited to any particular form or constructionof the parts except in so far as such limitations are specified in the claims.

Having thus described my invention, what Iclaimisz V V 1; In an expanding chuck for holding and supporting work pieces, the combination of a body provided with an axial opening therethrough, work holding jawsmounted for radial movement on said body and PI'O.

vided with active axial portions disposed intervals around said opening and formed on their outer sides with work gripping surfaces adapted to bear on the interior of the work and fixedly hold the same, said jaws having on their inner sides engaging surfaces sloping rearwardly and grooves bearing against the sides of the axial portions of the jaws and actin in conjunction therewith to exclude dust om the interior of the chuck, the form and relation of the parts being such that when the plunger is advanced between the jaws,

signature.

the latter will beexpanded into firm en- "gagement with the interior of the work and the plunger will give direct support to the overhanging active portions of the aws.

2. Ina chuck, the combination of a body, work holding jaws mounted therein J and movable to grip the work, a movable operating plunger adapted to engage the jaws to operate the same, andreleasablemeans for holding the plunger engaged with the jaws to maintain the latter in gripping position, said means adapted to engage the plunger and acton the jaws.

3.In a chuck, the combination of a body,

work holding jaws mounted therein and movable outwardly to grip the work, an operating plunger movable forwardly between thejaws to expand the same, and releasable means for .holdingtthe plunger forward with the jaws in gripping position, said means comprising a stem'screwed into the end of'the plunger, and a washer engaged by the'stem and bearing against the ends of the jaws.

In testimony whereof, I have aflixed my FRED E. BRIGHT. 

